This invention relates to the conversion of chemical energy to electrical energy and more particularly to a new and improved contact arrangement at the interface between the cathode and its current collector in electrochemical cells and batteries, herein referred to generally as electrochemical cells or simply as cells.
One area of use for the present invention is in electrochemical cells designed to provide electrical power to inaccessible devices such as implanted cardiac pacemakers. However, the present invention is applicable to a wide variety of batteries and electrochemical cells. It is particularly applicable to primary batteries intended to provide relatively high voltage and high energy density over long life under low current drain conditions.
In certain instances, dependant for the most part on the materials selected for the cell components, the cells of this invention may be assembled and encapsulated in a dry atmosphere, suitably in dry rooms or enclosures having a relative humidity less than about two percent, using substantially anhydrous and/or dried components. All of the cells and tests of cells described herein were prepared and performed substantially in sealed enclosures which, while not necessarily completely hermetic, did use substantially anhydrous components. In production embodiments, the electrochemical cells of this invention may be preferably enclosed in hermetically sealed enclosures such as welded stainless steel containers with appropriate electrical feedthrough arrangements for electrically contacting the cell components as is known in the art. The assembly of such cells preferably is accomplished in a dry room.